Illinois Digital Archives
Illinois Geologic Quadrangle Map
Base map compiled by Illinois State Geological Survey from digital data (Digital Line Graph) provided by the United States Geological Survey. Compiled by photogrammetric methods from imagery dated 1969. Field checked 1971. Revised from imagery dated 1993, 1995, and other sources. Field checked 1996.
North American Datum of 1983 (NAD 83)
Projection: Transverse Mercator
10,000-foot ticks: Illinois State Plane Coordinate system, west zone (Transverse Mercator)
1,000-meter ticks: Universal Transverse Mercator grid system, zone 16
Weibel, C.P., and F. Hardy, 2009, Soils and Parent Materials of Dunlap Quadrangle, Peoria County, Illinois: Illinois State Geological Survey, Illinois Geologic Quadrangle Map, IGQ Dunlap-SPM, 1:24,000.
Transfer of soil map units by Soil Survey staff, Natural Resources Conservation Service, Rock Falls, Illinois.
Digital cartography by Jennifer E. Carrell, Zahra Golshani, and Jane E.J. Domier, Illinois State Geological Survey.
The Illinois State Geological Survey and the University of Illinois make no guarantee, expressed or implied, regarding the correctness of the interpretations presented in this document and accept no liability for the consequences of decisions made by others on the basis of the information presented here. The geologic interpretations are based on data that may vary with respect to accuracy of geographic location, the type and quantity of data available at each location, and the scientific and technical qualifications of the data sources. Maps or cross sections in this document are not meant to be enlarged.
Soils and Parent Materials OF DUNLAP QUADRANGLE
PEORIA COUNTY, ILLINOIS
C. Pius Weibel and François Hardy
20091 / °12APPROXIMATE MEANDECLINATION, 2009MAGNETIC NORTHTRUE NORTHROAD CLASSIFICATIONPrimary highway,hard surfaceSecondary highway,hard surfaceLight-duty road, hard orimproved surfaceUnimproved roadInterstate RouteU.S. RouteState Route
4 Oak Hill
5 Spring Bay
6 Hanna City
7 Peoria West
8 Peoria East
BASE MAP CONTOUR INTERVAL 20 FEET
NATIONAL GEODETIC VERTICAL DATUM OF 1929
123456787000 FEET10001000020003000400050006000.51 KILOMETER10SCALE 1:24,0001/2101 MILE
© 2009 University of Illinois Board of Trustees. All rights reserved.
For permission information, contact the Illinois State Geological Survey.
Institute of Natural Resource Sustainability
William W. Shilts, Executive Director
ILLINOIS STATE GEOLOGICAL SURVEY
E. Donald McKay III, Interim Director
For more information contact:
Institute of Natural Resource Sustainability
Illinois State Geological Survey
615 East Peabody Drive
Champaign, Illinois 61820-6964
Soils and Parent Materials
The Soils and Parent Materials of Dunlap Quadrangle was developed from a recompilation of the Soil Survey of Peoria County (Walker 1992). The recompilation was produced specifically for the Illinois State Geological Survey (ISGS) under an agreement with the U.S. Department of Agriculture-Natural Resources Conservation Service (USDA-NRCS). The soil map unit boundaries (soil series) were transferred onto mylar overlays superimposed on 1:12,000-scale (quarter-quadrangle) prints of the 1998/99 Digital Orthophoto Quadrangles and the 1996 U.S. Geological Survey digital line graphics of the hypsography (contour lines). The mylar overlays with hand-drawn boundaries were then digitally scanned. The resulting raster image was translated into vector data using ArcInfo software at the ISGS. This process created a digital database to which various attributes of the soil series were added.
The soil series displayed on this map are organized by their parent material in the map legend using a soil key provided by the NRCS office in Champaign, Illinois (table 1). The map labels consist of numbers or of a combination of numbers and a letter. The initial numbers represent the number of each soil series. An uppercase letter following these numbers on the map indicates the class of slope: A, 0–2%; B, 2–5%; C, 5–10%; D, 10–15%; E, 15–25%; F, 25–35%; G, 35–60%. Map labels without a slope letter are for flat areas. A final number of 2 following the slope letter on the map indicates that the soil is moderately eroded, and a final number of 3 indicates that the soil is severely eroded. Because soil properties are closely related to the characteristics of their parent materials, the individual soil series are categorized within a USDA parent material class following the classification scheme of Fehrenbacher et al. (1984) and by reviewing updated soil series description sheets. The parent material classes and their descriptions were modified as needed to conform to information gathered during fieldwork for mapping the surficial geology of the quadrangle (Hardy and Weibel 2008). These classes generally correspond with the ISGS surficial geology mapping units.
Within each parent material class, the soil series (table 1) were further organized based upon the thickness of a silty or loamy surface cover, vegetation type under which they formed, and USDA drainage class. Each soil map unit is color-coded according to the soil association in which it belongs. Fehrenbacher et al. (1984) defined soil associations as a grouping of soils on the basis of the parent materials, their surface-soil color, degree of development, and natural soil drainage. Each association was named from two or more of the major statewide soils within the association (Fehrenbacher et al. 1984). Associations also contain numerous minor soils, some of which are in more than one association. The soils in an association tend to form a characteristic pattern on the landscape that is often repeated.
Map review was provided by Roger Windhorn, Natural Resources Conservation Service, Champaign, Illinois.
Fehrenbacher, J.B., J.D. Alexander, I.J. Jansen, R.G. Darmody, R.A. Pope, M.A. Flock, E.E. Voss, J.W. Scott, W.F. Andrews, and L.J. Bushue, 1984, Soils of Illinois: University of Illinois at Urbana-Champaign, College of Agriculture, Agricultural Experiment Station and U.S. Department of Agriculture, Soil Conservation Service, Bulletin 778, 85 p.
Hardy, F., and C.P. Weibel, 2008, Surficial geology of Dunlap Quadrangle, Peoria County, Illinois: Illinois State Geological Survey, Illinois Preliminary Geologic Map, IPGM Dunlap-SG, 1:24,000, report, 3 p.
Walker, M.B., 1992, Soil survey of Peoria County, Illinois: United States Department of Agriculture Soil Conservation Service, 225 p.
Thick loess (>80 inches)Moderately thick loess (40–80 inches) on loamy Wisconsin Episode till or lacustrine depositsModerately thick to thin loess or silty material (20–80 inches) on medium-textured, Wisconsin Episode outwashThin loess (10–40 inches) on loam, Wisconsin Episode tillThin loamy or silty materials on gravelly Wisconsin Episode outwashThick, sandy Wisconsin Episode outwash and aeolian materialsThin loess or loamy materials with or without residuum on interbedded sandstone, siltstone, and shaleSandy to clayey alluvial sediments on bottomlandsOrganic materials (peat and mucks)Tama-Ipava-SableCatlin-Flanagan-El PasoPlano-Proctor-Worthen(Drummer-minor soil)Saybrook-Dana-El Paso(Peotone-minor soil)Lorenzo-Warsaw-WeaSparta-Dickinson-OnargaLawson-Sawmill-DarwinHoughton-Palms-MuskegoFayette-Rozetta-StronghurstClinton-Keomah-RushvilleSt. Charles-Camden-DruryDodge-Russell-MiamiOakville-Lamont-AlvinDerinda-Schapville-EleroySoil parent materialsPrairie(dark and moderately dark)Timber(light and moderately dark)
Table 2 Soil associations of Illinois in the Dunlap Quadrangle (after Fehrenbacher et al. 1984).
py3(92) Tama (36)PIpava(43)PSable (68)PElkhart(567)PClarksdale(257)TRFayette(280)TRozetta2(279)(2279)TKeomah2(17)(2017)TRushville(16)TSylvan(19)TCatlin(171)PSaybrook(145)PDodge(24)THennepin(857)THickory(8)TStrawn2 (224)(857)(2224)TPlano(199)PElburn(198)PSt. Charles(243)TProctor(148)PStarks(132)TCamden(134)TWarsaw(290)PChute3(282)TRDickinson(87)PAlvin(131)TWorthen(37)PPeotone(330)PLena(210)Landes(304)Jules(28)Paxico(406)Dorchester(239)Huntsville(77)Lawson(451)Radford(74)Beaucoup4(3070)Sawmill(107)Denny (45)PElco (119)TDowns (386)TRAssumption (259)PDrummer(152)PVirgil (104)TRBrenton (149)PHarvard(344)TROrion (415)Marseilles (549)TLenzburg(871)Mine land regolith; material composed of a mixture of fine loamy sediments, till clasts, and fragments of bedrock (shale, sandstone, siltstone, coal, and limestone); gray to black, red to brown to yellow; occurs in areas where drift and uppermost bedrock have been excavated and deposited during surface mining activitiesLoess(0–20 inches thick)over glacial tillLoess(40–80 inches thick)over glacial outwashLoess(20–40 inches thick)over glacial outwashLoamy materials(20–40 inches thick)over sand and gravelLoess(>80 inches thick)Loess (40–80 inches thick) over glacial tillLoess(20–40 inches thick)over glacial tillFine sandor loamy fine sandLoamy sand(20–40 inches thick)over sand and loamy sandSilty materials(>80 inches thick)Silty and clayey materials(>40 inches thick)Loamy materials(20–40 inches thick) over loamy sand and sandAlluvium (silty)Sapric materials (muck)(>50 inches thick)Sand to loamy sand(>40 inches thick)Organic deposit; peat, organic silt, and mire; very dark gray to black; water saturated; accumulates in abandoned channels and depressions on stream floodplainsLoess or loamydeposits on siltstoneand shaleMine spoil (loamy)1 Type of natural vegetation cover often associated with each soil series is denoted by symbols: P, prairie; TR, transitional cover; T, timber (forested).2 Includes Urban land complexes of Keomah (17), Strawn (224), Rozetta (279), or Orthents (802).3 Soils that are excessively to somewhat excessively drained.4 Frequently flooded phase of Beaucoup (70).Loess; windblown silt deposit; dark grayish brown to yellowish brown; silt to silt loam; blankets upland; absent from lower, active geomorphic surfaces (e.g., stream channels and floodplains)Glacial till; sediment composed of a mixture of clay, silt, sand, and larger clasts of various sizes, deposited by glaciers; brown to grayish brown; loam and clay loam; hard to firm; blankets the area; absent where dissected by streams or removed by postglacial erosion; loess cover thin to absent on slopes due to erosionGlacial outwash; stratified to massive, proglacial fluvial sediments deposited by glacial meltwater; dominantly sand and gravelly sand, with minor loamy sand to silt loam and scattered cobbles, stones, and boulders; dark brown to yellow to grayish brown; found in terraces, channel bars, and floodplain and channel deposits in stream valleys; includes fine- to medium-grained sand deposits that have been reworked by aeolian processesColluvium; crudely stratified to massive deposits on slopes of valleys and depressions at base of slopes; dominantly formed by creep and secondarily by debris slides; dark grayish brown to yellowish brown silty or clayey deposits composed of remobilized loess, outwash and till, and, where drift is thin, minor amounts of bedrockAlluvium; recently (postglacial) deposited sediments, including buried soils, occurring on stream floodplains and terraces, channels, and upland drainages; includes fan-shaped deposits in areas where streams and ravines emerge from uplands onto lower-gradient floodplains; includes areas that are seasonally flooded; dark grayish brown to brown; yellowish brown to dark gray; massive to stratified; silty clay loam to sand and gravelly sand, may include remobilized humus, small calcare-ous shells, and dispersed small to large wood fragmentsBedrock residuum; weathered bedrock; may include a thin mantle of loess, till, or remobilized till; yellowish brown to olive-gray to grayish brown; massive; silt, silty clay loam, and clay loam mixed with fragments of shale, siltstone, and sandstoneMan-made land (human-disturbed deposits); Urban land consists of areas covered by streets, sidewalks, driveways, parking lots, buildings, and other structures that obscure the soils so that identification is not feasible; Gravel pits are areas from which gravel, sand, or both have been removed, including the surrounding area in which the mining by-products have been placedPoorlydrainedSomewhatpoorlydrainedModeratelywelldrainedExcessivelytowell drainedParent material classNatural soil drainage1Parent materials in soil profile (USDA)Loess (20-40 inches thick) on paleosolsORTHENTS2 (2802)Earth fill (loamy); materials generally in cut-and-fill areas; in the cut areas, topsoil has been removed and subsoil or underlying material has been exposed; in fill areas, additional loamy material has been placed on the original surface and in many cases has been mixed with the original soilURBAN LAND (533), GRAVEL PITS (865)
Table 1 Soil series (map unit) by parent materials and drainage class.
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